Ceramic coating heat shield for induction welding

ABSTRACT

An assembly is provided for induction welding. This assembly utilizes a heat shield (e.g., a mica heat shield) with a recess. An induction welding coil may be disposed within this heat shield recess during induction welding operations. The wall thickness of the heat shield within the recess may be reduced to enhance heat transfer to a workpiece during induction welding operations. The heat shield may be coated with a ceramic coating to enhance the heat shield&#39;s heat resistance and reduce heat shield flaking at the recess during induction welding operations.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation-in-part application of, claimspriority to and the benefit of, U.S. application Ser. No. 17/752,432,filed May 24, 2022 and entitled “INDUCTION WELDING HEAT SHIELD ASSEMBLYWITH MULTIPLE HEAT SHIELDS WITH ALIGNED RECESSES FOR INDUCTION WELDINGPATH”. The disclosure of U.S. application Ser. No. 17/752,432, filed May24, 2022, is incorporated by reference herein in entirety for allpurposes.

FIELD

This disclosure relates generally to induction welding and, moreparticularly, to temperature management between an induction weldingcoil and workpiece members being induction welded together.

BACKGROUND

A workpiece may be induction welded to bond workpiece members of theworkpiece together. Induction welding requires enhanced temperaturecontrol to prevent the top surface of the workpiece from burning, whilemaintaining a melting temperature at the bond line between an adjacentpair of workpiece members.

SUMMARY

An induction welder or induction welding assembly is disclosed herein.Both the configuration of such an induction welding assembly and theoperation of such an induction welding assembly are within the scope ofthis disclosure.

In various embodiments, the induction welding assembly may comprise aninduction welding coil, a heat shield (e.g., a mica heat shield), and aworkpiece zone. In various embodiments, the heat shield may comprise aceramic coating. In various embodiments, the heat shield may comprise aheat shield recess aligned with and projecting toward said inductionwelding coil. In various embodiments, said heat shield may be disposedbetween said induction welding coil and said workpiece zone in a firstdimension.

The ceramic coating may have a heat resistance greater than 900 degreesFahrenheit. In various embodiments, the ceramic coating may be anon-conductor of an electromagnetic field. In various embodiments, theceramic coating may be disposed along the heat shield recess. In variousembodiments, the ceramic coating may be a homogenous mixture of at leasttwo coatings. In various embodiments, the ceramic coating may furthercomprise polytetrafluoroethylene synthetic fluoropolymer. In variousembodiments, the heat shield may comprise mica. In various embodiments,the heat shield may be a non-conductor of an electro-magnetic field.

In various embodiments, the heat shield may comprise a first heat shieldend and a second heat shield end, said heat shield recess extendingbetween said first and second heat shield ends and projecting away fromsaid workpiece zone, wherein the heat shield recess is configured toprovide a welding path for said induction welding coil. In variousembodiments, the heat shield recess may comprise a pair of sidewalls anda base that extends between each sidewall of said pair and that furtherextends between said first and second heat shield ends.

In various embodiments, the induction welding coil may be at leastpartially disposed within said heat shield recess and may be spaced fromsaid base. In various embodiments, said base may be axially extendingbetween said first and second heat shield ends. In various embodiments,said base may be curved proceeding between said first and second heatshield ends. In various embodiments, the heat shield may comprise athickness within the heat shield recess that is at least substantiallyconstant proceeding between said first and second heat shield ends.

An induction welding assembly is also disclosed herein. In variousembodiments, the induction welding assembly may comprise an inductionwelding coil, a heat shield (e.g., a mica heat shield), and a workpiecezone. In various embodiments, the heat shield assembly may comprise aplurality of heat shields aligned in end-to-end relation. Each heatshield of said plurality of heat shields may comprise a heat shieldrecess. Each heat shield recess of said plurality of heat shields maycomprises a ceramic coating. In various embodiments, heat shieldrecesses of said plurality of heart shields may be aligned to provide awelding path for said induction welding coil. In various embodiments,said heat shield assembly may be disposed between said induction weldingcoil and said workpiece zone in a first dimension. In variousembodiments, said welding path may axially extending. In variousembodiments, said welding path may be curved.

An induction welding method is also disclosed herein. In variousembodiments, the induction welding method may comprise positioning aworkpiece such that a heat shield is disposed between said workpiece andan induction welding coil, wherein said induction welding coil is atleast partially disposed in a heat shield recess of said heat shield,wherein said heat shield comprises a ceramic coating, and wherein saidworkpiece comprises a first workpiece member and a second workpiecemember. In various embodiments, the method may comprise advancing saidinduction welding coil along a welding path along the heat shield,wherein a spacing between said induction welding coil and said heatshield remains at least substantially constant during said advancing. Invarious embodiments, the method may comprise operating said inductionwelding coil to induction weld said first workpiece member to saidsecond workpiece member.

In various embodiments, said first workpiece member may comprise a paneland said second workpiece member may comprise a stiffener. In variousembodiments, said panel may be curved about a reference axis such thatsaid advancing is also at least generally about said reference axis,wherein said advancing is at least generally along a length dimension ofsaid stiffener. In various embodiments, said stiffener may comprise aflange and said operating comprises induction welding said flange tosaid panel.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter of the present disclosure is particularly pointed outand distinctly claimed in the concluding portion of the specification.An understanding of the present disclosure may be further facilitated byreferring to the following detailed description and claims in connectionwith the following drawings. While the drawings illustrate variousembodiments employing the principles described herein, the drawings donot limit the scope of the claims. Reference to “in accordance withvarious embodiments” in this Brief Description of the Drawings alsoapplies to the corresponding discussion in the Detailed Description.

FIG. 1 is a side illustration of a portion of a system for inductionwelding a workpiece.

FIG. 2 is a schematic illustration of an induction welder arranged withthe workpiece.

FIG. 3 is a perspective illustration of a bottom support structure.

FIG. 4 is a cross-sectional illustration of the bottom supportstructure.

FIG. 5 is a cross-sectional illustration of a top support structure.

FIG. 6 is a perspective illustration of the top support structure.

FIG. 7 is a perspective illustration of a trunk.

FIG. 8 is a side view illustration of a set of the trunks arranged witha beam of the top support structure.

FIG. 9 is a perspective illustration of a heat shield.

FIG. 10 is a perspective illustration of a heat shield holder.

FIG. 11 is a perspective illustration of an induction welding fixtureconfigured with the bottom support structure and the top supportstructure.

FIG. 12 is a flow diagram of a method for induction welding theworkpiece.

FIG. 13 is a cross-sectional illustration of a portion of the inductionwelding system.

FIG. 14 is a cross-sectional illustration of a portion of the inductionwelding system during induction welding of a plurality of workpiecemembers together.

FIG. 15A is a sectional illustration of a portion of the top supportstructure engaging a workpiece with a planar configuration.

FIG. 15B is a sectional illustration of a portion of the top supportstructure engaging a workpiece with a non-planar configuration.

FIG. 16A is a perspective illustration of the induction welding fixturewith a rectangular configuration.

FIG. 16B is a perspective illustration of the induction welding fixturewith a non-rectangular configuration.

FIGS. 17A-17C are sectional illustrations of interfaces between variousdifferent workpiece members.

FIG. 18 is a schematic illustration of the induction welding systemconfigured with a plurality of top support structures.

FIG. 19A is a perspective view of a planar heat shield that incorporatesa recess.

FIG. 19B is a perspective view of a curved heat shield that incorporatesa recess.

FIG. 19C is a side end view of the heat shield of FIG. 19B.

FIG. 20 is a schematic of an induction welding assembly that utilizes aheat shield with a recess.

FIG. 21 is a flowchart that illustrates an induction welding method.

FIG. 22A illustrates a front-view profile of a stiffened panel half(such as for an aircraft nacelle fan cowl) having a semi-cylindricalgeometry.

FIG. 22B illustrates a section view of the panel half of FIG. 22A havinga rounded geometry.

FIG. 23A is a cross-sectional view of an induction welding assembly thatutilizes a plurality of heat shields arranged for movement of aninduction welding coil along a curved welding path.

FIG. 23B is a cross-sectional view of an induction welding assembly thatutilizes a plurality of heat shields arranged for movement of aninduction welding coil along an axial welding path.

FIG. 24 is a cross-sectional view of an induction welding assemblyhaving a heat shield and a plurality of workpiece members.

FIG. 25 is a cross-sectional view of an induction welding assemblyhaving a ceramic coated heat shield and a plurality of workpiecemembers.

FIGS. 26A and 26B are perspective views of a ceramic coated planar heatshield.

DETAILED DESCRIPTION

FIG. 1 illustrates a system 20 for induction welding a workpiece 22.This induction welding system 20 includes an induction welder 24 and aninduction welding fixture 26.

The induction welder 24 is configured to induction weld the workpiece22. More particularly, the induction welder 24 is configured toinduction weld two or more members 28A and 28B (generally referred to as“28”) of the workpiece 22 together, which workpiece members 28 may be(e.g., discretely formed) thermoplastic bodies or any other type ofinduction weldable bodies. The induction welder 24 of FIG. 1 includes apower source 30 and an induction coil assembly 32.

The power source 30 is configured to generate a periodic electricalcurrent. The power source 30, for example, may be configured as ahigh-frequency current source. The power source 30 may be or otherwiseinclude an alternating current (AC) generator, transformer, amplifier,etc. Alternatively, the power source 30 may include a direct current(DC) generator, transformer, amplifier, battery, etc. electricallycoupled with an oscillator. The present disclosure, however, is notlimited to such exemplary power sources.

Referring to FIG. 2 , the induction coil assembly 32 includes anelectrical first lead 34, an electrical second lead 36 and an inductionwelding coil 38. The first lead 34 may be arranged parallel with thesecond lead 36. The first lead 34 and the second lead 36 are connectedto opposing ends of the induction welding coil 38. The first lead 34 andthe second lead 36 electrically couple the induction welding coil 38 torespective terminals 40 and 42 of the power source 30.

The induction welding coil 38 may be configured as an elongated loop.The induction welding coil 38 of FIG. 2 , for example, extends along anon-straight (e.g., generally racetrack shaped) centerline between andto the coil ends. The induction welding coil 38 of FIG. 2 includes atleast one welding (e.g., bottom side) segment 44. This welding segment44 may be configured to substantially match an exterior surface contourof the workpiece 22 to be induction welded. The welding segment 44, forexample, may be straight where the workpiece 22 has a flat exteriorsurface 46. The welding segment 44 may alternatively be non-straight(e.g., curved, compound, etc.) where the workpiece exterior surface 46is a non-straight; e.g., curved, compound, etc. The present disclosure,however, is not limited to the foregoing exemplary induction weldingcoil configurations.

Referring to FIG. 1 , the induction welding fixture 26 is configured toposition and secure (e.g., temporarily, fixedly hold) the workpiece 22during induction welding. More particularly, the induction weldingfixture 26 is configured to position and secure the workpiece members 28together while those members 28 are induction welded together using theinduction welding coil 38.

The induction welding fixture 26 of FIG. 1 includes a first (e.g.,bottom, base) support structure 48 and a second (e.g., top, lid) supportstructure 50. For ease of description, the first support structure 48 isreferred to below as a “bottom support structure” and the second supportstructure 50 is referred to below as a “top support structure”. However,the present disclosure is not limited to such an exemplary orientationrelative to gravity. For example, in other embodiments, the supportstructure 50 may be arranged vertically below, or to a side of, thesupport structure 48.

Referring to FIG. 3 , the bottom support structure 48 includes a supportstructure base 52, a bottom heat management device 54 (e.g., a heat sinkor an insulator) and an actuator 56. The support structure base 52extends longitudinally (e.g., along an x-axis) between and to a firstend 58 of the support structure base 52 and a second end 60 of thesupport structure base 52. The support structure base 52 extendslaterally (e.g., along a y-axis) between and to a first side 62 of thesupport structure base 52 and a second side 64 of the support structurebase 52. The support structure base 52 extends vertically (e.g., along az-axis) between and to a bottom side 66 of the support structure base 52and a top side 68 of the support structure base 52.

Referring to FIG. 4 , the support structure base 52 is configured with areceptacle 70 adapted to receive the workpiece 22 (see FIG. 1 ). Thesupport structure base 52 is also configured with a channel 72configured to receive the bottom heat management device 54 and theactuator 56.

The workpiece receptacle 70 may be configured as a channel or adepression in the base top side 68. The workpiece receptacle 70 of FIG.4 , for example, is located at (e.g., on, adjacent or proximate) thebase top side 68, and intermediate (e.g., midway) laterally between theopposing base sides 62 and 64. The workpiece receptacle 70 extendsvertically into the support structure base 52 from the base top side 68to a receptacle end surface 74 of the support structure base 52. Theworkpiece receptacle 70 extends laterally within the support structurebase 52 between and to opposing receptacle side surfaces 76A and 76B(generally referred to as “76”) of the support structure base 52. Theworkpiece receptacle 70 extends longitudinally through (or within) thesupport structure base 52 between and to or about the opposing base ends58 and 60 (see FIG. 3 ).

The base channel 72 is also located at (e.g., on, adjacent or proximate)the base top side 68, and intermediate (e.g., midway) laterally betweenthe opposing base sides 62 and 64 and the opposing receptacle sidesurfaces 76. The base channel 72 of FIG. 4 , for example, extendsvertically into the support structure base 52 from the receptacle endsurface 74 to a channel end surface 78 of the support structure base 52.The base channel 72 extends laterally within the support structure base52 between and to opposing channel sides surfaces 80A and 80B (generallyreferred to as “80”) of the support structure base 52. The base channel72 extends longitudinally through (or within) the support structure base52 between and to or about the opposing base ends 58 and 60 (see FIG. 3). The support structure base 52 of the present disclosure, however, isnot limited to such an exemplary channel configuration. For example, inother embodiments, the base channel 72 may extends vertically into thesupport structure base 52 from the base top side 68 where, for example,the workpiece receptacle 70 is omitted.

The support structure base 52 may be constructed from a non-electricallyconductive material. This non-electrically conductive material may be apolymer such as, but not limited to, polyurethane. The presentdisclosure, however, is not limited to the foregoing exemplary supportstructure base materials.

The bottom heat management device 54 may be or otherwise include a heatsink configured to absorb heat energy. The bottom heat management device54, for example, may be constructed from a ceramic such as, but notlimited to, aluminum silicate (also referred to as alumina silicate).The present disclosure, however, is not limited to the foregoingexemplary first heat sink materials. Furthermore, in other embodiments,the bottom heat management device 54 may be or otherwise include aninsulator. The heat management device 54, for example, may be configuredto absorb and/or block transfer of heat energy.

The bottom heat management device 54 of FIG. 4 extends laterally betweenand to a first side 82 of the bottom heat management device 54 and asecond side 84 of the bottom heat management device 54. The bottom heatmanagement device 54 extends vertically between and to a bottom side 86of the bottom heat management device 54 and a top side 88 of the bottomheat management device 54. Referring to FIG. 3 , the bottom heatmanagement device 54 extends longitudinally between and to opposing ends90A and 90B (generally referred to as “90”) of the bottom heatmanagement device 54).

The bottom heat management device 54 of FIG. 4 is mated with (e.g.,received within) the base channel 72. The heat management device firstside 82 is abutted laterally against and moveable (e.g., slidable) alongthe channel first side surface 80A. The heat management device secondside 84 is abutted laterally against and moveable (e.g., slidable) alongthe channel second side surface 80B. The heat management device bottomside 86 faces the channel end surface 78. The heat management device topside 88 faces away from the support structure base 52; e.g., in avertical upwards direction.

The actuator 56 is mated with (e.g., received within) the base channel72, and arranged vertically between the channel end surface 78 and thebottom heat management device 54. The actuator 56 is configured to push(e.g., bias) the bottom heat management device 54 vertically away fromthe support structure base 52 and its channel end surface 78. Theactuator 56 of FIG. 4 , for example, is configured as an expandablepressure vessel 92; e.g., fluid bladder such as, but not limited to, anexpandable air tube, an expandable air bag, etc. This pressure vessel 92is connected to a fluid source 94; e.g., a compressed air reservoir(e.g., a tank) and/or an air pump. The pressure vessel 92 is configuredto receive fluid (e.g., compressed air) from the fluid source 94, whereregulation of the fluid may cause the pressure vessel 92 to expand orcontract in size. When the pressure vessel 92 expands in size, the fixedchannel surfaces 78 and 80 may cause the pressure vessel 92 to expand ina vertically upward direction and thereby push the bottom heatmanagement device 54 vertically within the base channel 72 away from thechannel end surface 78. However, when the pressure vessel 92 contractsin size, the pressure vessel 92 may contract in a vertically downwarddirection and the bottom heat management device 54 may move verticallywithin the base channel 72 towards from the channel end surface 78.

In some embodiments, a spacer 96 may be disposed within the base channel72 vertically between the pressure vessel 92 and the bottom heatmanagement device 54. This spacer 96 may be configured to provide athermal break/a thermal insulator between the bottom heat managementdevice 54 and the pressure vessel 92. The spacer 96, for example, may beconstructed from a thermally insulating material such as, but notlimited to, silicon.

Referring to FIG. 5 , the top support structure 50 includes a frame 98,a plurality of trunks 100 and a top heat management device or heatshield 102. The top support structure 50 of FIG. 5 also includes a topheat shield holder 104.

Referring to FIG. 6 , the support structure frame 98 extendslongitudinally between and to a first end 106 of the support structureframe 98 and a second end 108 of the support structure frame 98. Thesupport structure frame 98 extends laterally between and to a first side110 of the support structure frame 98 and a second side 112 of thesupport structure frame 98. The support structure frame 98 extendsvertically between and to a bottom side 114 of the support structureframe 98 and a top side 116 of the support structure frame 98.

The support structure frame 98 of FIG. 6 includes one or more framebeams 118A and 118B (generally referred to as “118”). These frame beams118 are arranged parallel with one another. Each of the frame beams 118extends longitudinally between and to (or about) the opposing frame ends106 and 108. Each of the frame beams 118 extends vertically between andto the opposing frame sides 114 and 116. The first beam 118A is arrangedat (e.g., on, adjacent or proximate) the frame first side 110. Thesecond beam 118B is arranged at (e.g., on, adjacent or proximate) theframe second side 112. The first beam 118A and the second beam 118B arelaterally displaced from one another by an inter-beam channel 120.

Referring to FIG. 5 , each of the frame beams 118 may have a channeled(e.g., C-channel) cross-sectional geometry when viewed, for example, ina plane perpendicular to the longitudinal x-axis; e.g., plane of FIG. 5. The support structure frame 98 of the present disclosure, however, isnot limited to such an exemplary frame beam configuration.

The support structure frame 98 and each of its beams 118 may beconstructed from metal such as, but not limited to, steel. The presentdisclosure, however, is not limited to such exemplary support structureframe materials.

Referring to FIG. 7 , each trunk 100 may be configured as a supportblock. Each trunk 100, for example, extends longitudinally between andto a first end 122 of the respective trunk 100 and a second end 124 ofthe respective trunk 100. Each trunk 100 extends laterally between afirst side 126 of the respective trunk 100 and a second side 128 of therespective trunk 100. Each trunk 100 extends vertically between a bottomside 130 of the respective trunk 100 and a top side 132 of therespective trunk 100.

Each trunk of FIG. 7 includes a trunk base 134 and a trunk protrusion136; e.g., a clamp head. Each of these trunk elements 134 and 136 mayextend longitudinally between and to the opposing trunk ends 122 and124.

The trunk base 134 is arranged at (e.g., on, adjacent or proximate) thetrunk top side 132. The trunk base 134 of FIG. 7 , for example, extendsvertically from the trunk top side 132 towards the trunk bottom side130. This trunk base 134 extends laterally between and to the opposingtrunk sides 126 and 128. At least a portion 138 (or an entirety) of thetrunk base 134 may be laterally tapered. The trunk portion 138 of FIG. 7, for example, laterally tapers as the trunk base 134 extends verticallyto the trunk top side 132. This tapered configuration provides the trunkbase 134 with a canted exterior surface 140 extending along the trunksecond side 128. This second side surface 140 is angularly offset froman exterior surface 142 of the trunk 100 extending along the trunk topside 132 by an included angle; e.g., an obtuse angle. The second sidesurface 140 is angularly offset from an exterior surface 144 of thetrunk 100 extending along the trunk first side 126 by an included angle;e.g., an acute angle. The first side surface 144, by contrast, may beconfigured perpendicular to the top side surface 142.

The trunk protrusion 136 is arranged at (e.g., on, adjacent orproximate) the trunk bottom side 130. The trunk protrusion 136 of FIG. 7, for example, projects vertically out from the trunk base 134 to thetrunk bottom side 130. The trunk protrusion 136 is arranged at (e.g.,on, adjacent or proximate) the trunk second side 128. The trunkprotrusion 136 of FIG. 7 , for example, projects laterally from thetrunk second side 128 to a side 146 of the trunk protrusion 136 which islaterally displaced from the trunk first side 126.

Each trunk 100 may be constructed from a non-electrically conductivematerial. This non-electrically conductive material may be a polymersuch as, but not limited to, polyurethane. The present disclosure,however, is not limited to the foregoing exemplary trunk materials.

Referring to FIG. 5 , the trunks 100 are arranged within the inter-beamchannel 120. Referring to FIG. 8 , each of the frame beams 118 isconfigured with a set (e.g., a row) of one or more of the trunks 100.Each set of the trunks 100, for example, may be arranged end-to-endlongitudinally along a respective one of the frame beams 118, where thetrunk first sides 126 laterally engage (e.g., contact, abut) therespective frame beam 118; see FIG. 5 .

Referring to FIGS. 5 and 6 , each of the trunks 100 is connected to therespective frame beam 118 in a repositionable manner. For example, eachtrunk 100 of FIGS. 5 and 6 is secured to the respective frame beam 118by a quick release coupler 148 and one or more fastener assemblies 150;e.g., bolt and nut assemblies. Each of these connectors 148 and 150 maybe mated with a respective aperture (e.g., slot) in a web of the framebeam 118, which aperture is sized to facilitate vertical (e.g., up anddown) movement of the trunk 100 along the respective frame beam 118 andits web. The quick release coupler 148 is configured to temporarilymaintain a vertical position of the respective trunk 100 along therespective frame beam 118 while the fastener assemblies 150 are loose.The fastener assemblies 150 are configured to fix the vertical positionof the respective trunk 100 for the induction welding of the workpiece22 (see FIG. 1 ). Each of the fastener assemblies 150, for example, maybe tightened to clamp the respective trunk 100 laterally against therespective frame beam 118 and its web and thereby fix the verticalposition of the trunk 100.

Referring to FIG. 9 , the top heat shield 102 is configured as acomponent operable to absorb heat energy. The top heat shield 102, forexample, may be constructed from a ceramic such as, but not limited to,aluminum silicate (also referred to as alumina silicate). The presentdisclosure, however, is not limited to the foregoing exemplary top heatshield materials.

The top heat shield 102 of FIG. 9 extends longitudinally between and toa first end 152 of the top heat shield 102 and a second end 154 of thetop heat shield 102. The top heat shield 102 extends laterally betweenand to a first side 156 of the top heat shield 102 and a second side 158of the top heat shield 102. The top heat shield 102 extends verticallybetween and to a bottom side 160 of the top heat shield 102 and a topside 162 of the top heat shield 102.

The top heat shield 102 may be laterally tapered. The top heat shield102 of FIG. 9 , for example, laterally tapers as the top heat shield 102extends vertically from the heat shield top side 162 to the heat shieldbottom side 160. The top heat shield 102 of FIG. 9 , for example, has a(e.g., isosceles) trapezoidal cross-sectional geometry when viewed, forexample, in a plane perpendicular to the longitudinal x-axis. Thepresent disclosure, however, is not limited to such an exemplary secondheat shield configuration.

Referring to FIG. 10 , the heat shield holder 104 extends longitudinallybetween and to a first end 164 of the heat shield holder 104 and asecond end 166 of the heat shield holder 104. The heat shield holder 104extends laterally between and to a first side 168 of the heat shieldholder 104 and a second side 170 of the heat shield holder 104. The heatshield holder 104 extends vertically between and to a bottom side 172 ofthe heat shield holder 104 and a top side 174 of the heat shield holder104.

The heat shield holder 104 of FIG. 10 is configured with a trunk recess176 and a heat shield receptacle 178. Each of these holder apertures 176and 178 may extend longitudinally through (or within) the heat shieldholder 104 between the opposing ends 164 and 166.

The trunk recess 176 is arranged at (e.g., on, adjacent or proximate)the holder top side 174, and intermediate (e.g., midway) laterallybetween the opposing holder sides 168 and 170. The trunk recess 176 ofFIG. 10 , for example, extends vertically into the heat shield holder104 from the holder top side 174 to a recess end surface 180 of the heatshield holder 104. The trunk recess 176 extends laterally within theheat shield holder 104 between and to opposing recess side surfaces 182Aand 182B (generally referred to as “182”) of the heat shield holder 104.In some embodiments, the opposing recess side surfaces 182 may have anarcuate cross-sectional geometry when viewed, for example, in a planeperpendicular to the longitudinal x-axis.

The heat shield receptacle 178 is located at (e.g., on, adjacent orproximate) the holder bottom side 172, and intermediate (e.g., midway)laterally between the opposing holder sides 168 and 170 and the opposingrecess side surfaces 182. The heat shield receptacle 178 of FIG. 10 ,for example, extends vertically into the heat shield holder 104 from therecess end surface 180 to the holder bottom side 172. The heat shieldreceptacle 178 extends laterally within the heat shield holder 104between and to opposing receptacle side surfaces 184A and 184B(generally referred to as “184”) of the heat shield holder 104. Each ofthese receptacle side surfaces 184 may be a canted surface. Each of thereceptacle side surfaces 184, for example, may be angularly offset froma surface 186 extending along the holder bottom side 172 by an includedangle; e.g., an acute angle. The heat shield receptacle 178 may therebyhave, for example, a (e.g., isosceles) trapezoidal cross-sectionalgeometry when viewed, for example, in a plane perpendicular to thelongitudinal x-axis. This trapezoidal cross-sectional geometry may besimilar to the trapezoidal cross-sectional geometry of the top heatshield 102 of FIG. 9 in shape, but may be slightly larger in size asshown in FIG. 5 .

The heat shield holder 104 may be constructed from a non-electricallyconductive material. This non-electrically conductive material may be apolymer such as, but not limited to, polyurethane. The presentdisclosure, however, is not limited to the foregoing exemplary heatshield holder materials.

Referring to FIG. 5 , the heat shield holder 104 is connected to thesupport structure frame 98 at the frame bottom side 114. The heat shieldholder 104, for example, is connected (e.g., mechanically fastened,bonded and/or otherwise attached) to flanges of the frame beams 118 atthe frame bottom side 114.

The top heat shield 102 is mated with (e.g., received within) the heatshield receptacle 178 (see FIG. 10 ). The receptacle side surfaces 184laterally overlap end portions of the top heat shield 102. Thereceptacle side surfaces 184 may thereby locate and vertically supportthe top heat shield 102 in its mated position. The trunks 100 may alsobe vertically positioned such that their projections 136 verticallyengage (e.g., contact) and/or abut against the heat shield top side 162.The trunks 100 may thereby retain the top heat shield 102 within theheat shield receptacle 178 (see FIG. 10 ). The trunks 100 also provide asupport (e.g., a backstop) for the top heat shield 102 during inductionwelding as described below in further detail.

Referring to FIG. 11 , the bottom support structure 48 may be mounted ona (e.g., fixed, stationary) base structure 188; e.g., a mounting block.The base structure 188 of FIG. 11 is configured to vertically elevatethe bottom support structure 48 off of a floor 190; e.g., a metal plateor pan. The base structure 188 is also configured to provide mountingareas for fixture accessories 192 such as, but not limited to, valvingand/or gauges for controlling and/or monitoring the actuator 56. Note,connections (e.g., conduits) between the elements 56 and 192 are omittedfor clarity of illustration.

The top support structure 50 may be configured as part of a gantry 194.The gantry 194 of FIG. 11 is configured to move laterally (e.g., alongthe y-axis) along one or more tracks 196 (e.g., rails), which tracks 196are disposed on opposing lateral sides of the base structure 188 andconnected to the floor 190. The gantry 194 of FIG. 11 includes one ormore vertical supports 198A and 198B (generally referred to as “198”);e.g., side frames. The top support structure 50 is vertically displacedfrom (e.g., positioned vertically above) the bottom support structure48. The top support structure 50 is arranged longitudinally between andconnected to the vertical supports 198. The top support structure 50 ofFIG. 11 is configured to move vertically (e.g., along the z-axis) alongone or more tracks 200 (e.g., rails), which tracks 200 are respectivelyconnected to and extend vertically along the vertical supports 198. Oneor more actuators (e.g., hydraulic cylinders) may be configured to movethe top support structure 50 along the tracks 200. One or more actuators(e.g., hydraulic cylinders) may also or alternatively be configured tomove the gantry 194 along the tracks 196. Of course, in otherembodiments, the top support structure 50 and/or the gantry 194 may bemanually moveable.

FIG. 12 is a flow diagram of a method 1200 for induction welding aworkpiece; e.g., the workpiece 22. This method 1200 may be performedusing an induction welding system such as, but not limited to, theinduction welding system 20 of FIG. 1 .

In step 1202, the induction welding fixture 26 and the workpiece 22 arearranged together. The workpiece 22 and its members 28, for example, maybe arranged vertically between the bottom support structure 48 and thetop support structure 50. For example, referring to FIG. 13 , theworkpiece 22 may be arranged within the workpiece receptacle 70. Aportion of the first workpiece member 28A may laterally andlongitudinally overlap (e.g., lap) a portion of the second workpiecemember 28B. One or more workpiece shims 202 and 204 may be provided tosupport the workpiece members 28, which workpiece shims 202 and 204 maybe constructed from a composite material such as fiberglass embeddedwithin an epoxy matrix. Each of these shims 202 and 204 may be arrangedwithin the workpiece receptacle 70 with the workpiece 22. The bottomshim 202 of FIG. 13 , for example, is located laterally adjacent (e.g.,abutted against) a lateral edge of the first workpiece member 28A. Thisbottom shim 202 is located vertically between and engages (e.g.,contacts) the receptacle end surface 74 and the second workpiece member28B. The top shim 204 of FIG. 13 is located laterally adjacent (e.g.,abutted against) a lateral edge of the second workpiece member 28B. Thistop shim 204 is located vertically on a (e.g., top) surface 206 of thefirst workpiece member 28A.

In step 1204, the workpiece 22 is secured vertically between the bottomsupport structure 48 and the top support structure 50. The top supportstructure 50 of FIG. 11 , for example, may be moved along the tracks 200until the top support structure 50 engages (e.g., contacts) one or moreof the elements 22, 28B, 204; e.g., see FIGS. 1 and 13 . The heat shieldholder 104 of FIG. 1 , for example, may vertically contact a top surface208 of the support structure base 52 at its top end 68. Referring toFIG. 13 , the heat shield holder 104 may vertically contact a topsurface 210 of the second workpiece member 28B and a top surface 212 ofthe top shim 204. A bottom workpiece contact surface 214 of the top heatshield 102 may abut vertically against and contact the second workpiecemember surface 210 and/or the second shim surface 212. The top heatshield 102 may thereby engage a top side of the workpiece 22 and its topsurface 46.

The trunks 100 may be adjusted vertically such that the trunkprotrusions 136 engage (e.g., contact) a top surface 216 of the top heatshield 102, which surface 216 is vertically opposite the heat shieldsurface 214. The trunks 100 may thereby provide a backstop for the topheat shield 102 as well as retain the top heat shield 102 against theworkpiece 22 and its members 28.

The actuator 56 may be actuated (e.g., inflated) to move (e.g., push)the elements 54 and 96 vertically upwards within the base channel 72towards the workpiece 22. This movement may cause the bottom heatmanagement device 54 to vertically engage (e.g., contact) at least theworkpiece 22 at a bottom side thereof. More particularly, a topworkpiece contact surface 218 of the bottom heat management device 54may abut vertically against and contact a bottom surface 220 of thefirst workpiece member 28A. The actuator 56 may be actuated further suchthat the workpiece 22 and its overlapping members 28 are pressed (e.g.,clamped) vertically between the support structures 48 and 50 and theirheat management devices 54 and 102. The workpiece 22 and its members 28may thereby be secured (e.g., clamped) vertically between the supportstructures 48 and 50 and, more particularly, the heat management devices54 and 102 using the trunks 100 as a backstop/anchor for the top heatshield 102.

In step 1206, the workpiece 22 is induction welded. The inductionwelding coil 38, for example, may be arranged in the channel 120 betweenthe trunks 100 such that the welding segment 44 is parallel with andslightly elevated from the heat shield surface 216. Once in position,the power source 30 (see FIG. 1 ) may provide a high frequency (e.g.,alternating) current to the induction welding coil 38. The inductionwelding coil 38 may subsequently generate electromagnetic waves whichexcite one or more reinforcement fibers within the first workpiecemember 28A via eddy currents and/or one or more of reinforcement fiberswithin the second workpiece member 28B via eddy currents. Thisexcitation may elevate a temperature of the first workpiece member 28Aand/or the second workpiece member 28B to a melting point temperaturewhere a polymer (e.g., thermoplastic) matrix of the first workpiecemember 28A and/or a polymer (e.g., thermoplastic) matrix of the secondworkpiece member 28B melts. Referring to FIG. 14 , a melt layer may format an interface 222 (e.g., a weld joint/seam) between the firstworkpiece member 28A and the second workpiece member 28B. This meltlayer may bond the first workpiece member 28A and the second workpiecemember 28B together upon cooling thereof.

The induction welding coil 38 may be moved longitudinally (e.g., in thex-axis direction) to provide an elongated welded seam between the firstworkpiece member 28A and the second workpiece member 28B. As theinduction welding coil 38 moves longitudinally, the induction weldingcoil 38 translates longitudinally within the channel 120 along thetrunks 100 on either side thereof.

By securing the workpiece 22 between the support structures 48 and 50and their heat management devices 54 and 102 during the inductionwelding, the induction welding fixture 26 may maintain contact betweenthe workpiece members 28 being welded together. The induction weldingfixture 26 may also maintain a compressive force across the overlapjoint between the workpiece members 28 to facilitate improved fusion.The heat management devices 54 and 102 may also or alternatively provideuniform heat for welding at the interface 222.

In step 1208, the workpiece 22 is released from the induction weldingfixture 26. The actuator 56 of FIG. 13 , for example, may be actuated(e.g., deflated) such that the bottom heat management device 54 moves(e.g., inwards) away from the workpiece 22. The top support structure 50may then be moved vertically (e.g., upwards) away from the workpiece 22.The now fused workpiece 22 may subsequently be removed from theinduction welding fixture 26. Alternatively, the induction weldingfixture 26 and the workpiece 22 may be rearranged to induction weld theworkpiece 22 at another location; e.g., another location laterally alongthe workpiece 22. The steps 1204, 1206 and 1208 may be repeated at thisother location to further induction weld the workpiece 22. For example,the first and the second workpiece members 28 may be welded togetheragain at the other location to provide another weld seam. Alternatively,one or more other members 28 of the workpiece 22 may alternatively beinduction welded together.

To accommodate induction welding of the workpiece 22 at multiplelocations and/or induction welding workpieces 22 with various differentconfigurations, the induction welding fixture 26 of the presentdisclosure is configured with multiple adjustable components. Forexample, the top support structure 50 may be moved laterally (e.g., viathe gantry 194) and/or vertically to facilitate placement of theworkpiece 22 with the induction welding fixture 26. The top supportstructure 50 may also or alternatively be moved to accommodate differentworkpiece thicknesses. The trunks 100 may be adjusted vertically foradjusting the backstop position of the top heat shield 102. The trunks100 may also be adjusted vertically for removal and replacement of thetop heat shield 102. One or more of the trunks 100 may also be swappedout (e.g., exchanged) for replacement trunks 100. By replacing the topheat shield 102 and/or the trunks 100, the induction welding fixture 26may accommodate workpieces with different surface geometries (e.g.,planar, curved or otherwise) along the overlap joint or the sameworkpiece with different surface geometries at different weld locations.For example, referring to FIG. 15A, where the exterior surface 210 ofthe workpiece 22 is planar (e.g., flat), a bottom (e.g., heat shieldengagement) surface 224 of each trunk protrusion 136 and/or the heatshield surface 214, 216 may also be planar. Referring to FIG. 15B, wherethe exterior surface 210 of the workpiece 22 is curved, one or more ofthe trunk protrusions surfaces 224 and/or the heat shield surface 214,216 may also be curved. Similarly, the bottom heat management device 54and/or the workpiece shims 202 and 204 may be replaced depending uponthe specific geometry of the workpiece 22 to be induction welded. Inaddition or alternatively, the support structure base 52 may also oralternatively be replaced in order to accommodate induction welding ofworkpieces with different configurations.

The method is described above as the induction welding fixture 26 beingstationary and the workpiece 22 being moveable to adjust the position ofthe workpiece 22 relative to the induction welding fixture 26. However,in other embodiments, the workpiece 22 may be stationary and theinduction welding fixture 26 may be moveable to adjust the position ofthe induction welding fixture 26 relative to the workpiece 22. In stillother embodiments, both the induction welding fixture 26 and theworkpiece 22 may be moveable for increasing adjustment options.

In some embodiments, the induction welding fixture 26 may have agenerally rectangular configuration as shown in FIG. 16A (see also FIG.1 ). In other embodiments, the induction welding fixture 26 may have anon-rectangular configuration as shown in FIG. 16B. The inductionwelding fixture 26 of FIG. 16B, for example, may be particularly suitedfor induction welding curved (e.g., arcuate) workpieces. The beams 118and/or the base 52, for example, may be curved or include curvedportions.

The method 1200 and the induction welding system 20 of the presentdisclosure may be utilized for induction welding various different typesand configurations of workpieces 22. For example, the workpiece 22 maybe configured as a fan cowl for a nacelle of an aircraft propulsionsystem. The workpiece 22, however, may alternatively be configured as ormay otherwise be included as part of another nacelle component, anaircraft control surface, a wing or an aircraft fuselage. The presentdisclosure, however, is not limited to induction welding andmanufacturing such exemplary components or to aircraft propulsion systemapplications. For example, the method 1200 and the induction weldingsystem 20 may be utilized for manufacturing any type or configuration ofworkpiece where two or more bodies (e.g., workpiece members 28) arejoined together via induction welding.

In some embodiments, referring to FIG. 17A, the workpiece members 28 maybe configured as planar or non-planar (e.g., curved) sheets of material.In other embodiments, referring to FIGS. 17B and 17C, any one or more ofthe workpiece members 28 (e.g., 28B) may be configured with more complex(e.g., convoluted, bent, etc.) geometry. The workpiece member 28B ofFIG. 17B, for example, is configured with an L-shaped cross-sectionalgeometry, for example, to provide the workpiece with a flange. Theworkpiece member 28B of FIG. 17C is configured with a channeled (e.g.,top-hat shaped) geometry, for example, to provide the workpiece 22 witha stiffener, a mount and/or a channel. The present disclosure, however,is not limited to the foregoing exemplary workpiece memberconfigurations.

In some embodiments, referring to FIG. 18 , the bottom support structure48 may be configured as a mobile unit. The base structure 188 of FIG. 18, for example, includes one or more wheels 226. These wheels 226 areconnected to the base structure 188 at a bottom surface 228 of the basestructure 188. The wheels 226 may be operable to move freely on thefloor 190. Alternatively, the wheels 226 may run on one or more tracks230. With such an arrangement, the bottom support structure 48 may bemoved within/into or out of a gantry tunnel 232 to provide additionaladjustment and/or facilitate placement and/or removal of the workpiece(not shown in FIG. 18 ).

In some embodiments, the induction welding fixture 26 may include aplurality of the top support structures 50 (schematically shown in FIG.18 ). Each of these top support structures 50 may be arranged with arespective gantry 194, where each gantry 194 may be fixed to the floor190. With this arrangement, the top support structures 50 may beconfigured with different trunks 100 (see FIG. 5 ). The top supportstructures 50, for example, may be setup to align with respectiveportions of the workpiece (not shown in FIG. 18 ) with differentgeometries. A larger portion or an entirety of the workpiece may therebybe induction welded without requiring readjustment of a single topsupport structure 50. In addition or alternatively, different locationson the workpiece may be induction welded concurrently; e.g.,simultaneously.

While the multiple gantries 194 shown in FIG. 18 are configured as fixedgantries, it is contemplated that one or more of these gantries 194 mayalternatively be mobile. Each of the gantries 194 in FIG. 18 , forexample, may alternatively be configured to move along tracks 196 asshown, for example, in FIG. 11 . Each gantry 194 and its respective topsupport structure 50 may thereby move relative to the bottom supportstructure 48 and/or relative to the other gantry 194 and its respectivetop support structure 50.

FIG. 18 illustrates the induction welding fixture 26 with two gantries194 and two respective top support structures 50. It is contemplated,however, the induction welding fixture 26 may include three or moregantries 194 and/or three or more top support structures 50.Furthermore, while the induction welding fixture 26 is illustrated witha single base structure 188 and a single bottom support structure 48,the present disclosure is not limited to such exemplarilyconfigurations. For example, in addition to or alternatively toincluding more than one gantry 194/more than one top support structure50, the induction welding fixture 26 may also include two or more basestructures 188 and/or two or more bottom support structures 48.

FIG. 19A illustrates a variation of the above-noted heat shield 102 andis identified by reference numeral 102 a. Corresponding components areidentified by the same reference numbers, and the foregoing discussionapplies unless otherwise noted to the contrary herein. The heatmanagement device or heat shield 102 a may be used in place of the heatshield 102 described above (and may be adapted accordingly).

The heat shield 102 a may be referenced in relation to a first dimension380 (the above-noted z direction or dimension), a second dimension 382(the above-noted y direction or dimension), and a third dimension 384(the above-noted x direction or dimension). The heat shield 102 aextends between the first heat shield end 152 and the second heat shieldend 154, where these ends 152, 154 are spaced from one another in thethird dimension 384 (e.g., coinciding with a length dimension for theheat shield 102 a). A width of the heat shield 102 a extendsin/coincides with the second dimension 382, while a thickness of theheat shield 102 a extends in/coincides with the first dimension 380 (thespacing between a first surface 306 (e.g., flat or planar) and anoppositely disposed second surface 308 (e.g., flat or planar) of theheat shield 102 a being in the thickness dimension).

A heat shield recess 300 is incorporated on the first surface 306 of theheat shield 102 a, and is concave on/relative to this first surface 306.The heat shield recess 300 is collectively defined by a pair ofsidewalls 302 that are spaced from one another in the second dimension382, along with a base or bottom 304 that extends between the sidewalls302. The sidewalls 302 and base 304 define the perimeter or boundary ofthe heat shield recess 300 and may be of any appropriate shape.

FIG. 19B and FIG. 19C illustrate a variation of the above-noted heatshield 102 and is identified by reference numeral 102 b. Correspondingcomponents are identified by the same reference numbers, and theforegoing discussion applies unless otherwise noted to the contrary. Theheat management device or heat shield 102 b may be used in place of theheat shield 102 described above (and may be adapted accordingly). In anycase, the heat shield 102 b is also a variation of the heat shield 102 aof FIG. 19A. The primary differences between the heat shield 102 a ofFIG. 19A and the heat shield 102 b of FIG. 19B and FIG. 19C include: 1)that the surface 308′ of the heat shield 102 b is curved proceeding fromthe first heat shield end 152 to the second heat shield end 154 (versusflat in the case of surface 308 for the heat shield 102 a); 2) the base304′ of the recess 300′ is curved proceeding from the first heat shieldend 152 to the second heat shield end 154 in the case of the heat shield102 b, and as such the height of the sidewalls 302′ may vary proceedingalong length of the recess 300′ (versus the base 304 being flat in thecase of the heat shield 102 a); and 3) the surfaces 306, 308′ of theheat shield 102 b are of different shapes in the case of the heat shield102 b (versus the surfaces 306, 308 being the same shape and parallel toone another in the case of the heat shield 102 a).

The first surface 306 for each of the heat shields 102 a, 102 b (outsidethe heat shield recess 300, 300′, respectively) may becorrespondingly-shaped with one or more supports (e.g., trunks) that mayengage the heat shield 102 a/102 b on opposite sides of the heat shieldrecess 300/300′ during induction welding operations, while the secondsurface 308/308′ may be correspondingly-shaped with a correspondingsurface of the workpiece being induction welded. In this regard and asrepresentatively illustrated in FIG. 19A for the case of the heat shield102 a, the second surface 308 may be flat or planar within a referenceplane that includes the second dimension 382 and the third dimension384, while the oppositely-disposed first surface 306 may also be flat orplanar within a reference plane that contains the second dimension 382and the third dimension 384, including where the surfaces 306, 308 areparallel. For the case of the heat shield 102 b shown in FIG. 19B andFIG. 19C, the second surface 308′ may be curved proceeding from thefirst heat shield end 152 to the oppositely disposed second heat shieldend 154 (e.g., curved proceeding in the third dimension 384) and/or maybe curved proceeding in the second dimension 382, while theoppositely-disposed first surface 306 is flat or planar within areference plane that contains the second dimension 382 and the thirddimension 384. As such, the surfaces 306, 308′ are of different shapesfor the case of the heat shield 102 b.

The base 304 of the heat shield recess 300 may be correspondingly-shapedwith and parallel to the second surface 308 of the heat shield 102 a.The thickness of the heat shield 102 a within the heat shield recess 300is then at least substantially constant proceeding from the first heatshield end 152 to the second heat shield end 154, which coincides withthe direction of an induction welding operation using the heat shield102 a. As such, the spacing between an induction coil and the workpiecebeing induction welded remains at least substantially constant as theinduction coil moves along the length dimension of the heat shieldrecess 300 during induction welding operations when using the heatshield 102 a (this length dimension coinciding with the spacing betweenthe first heat shield end 152 and the second heat shield end 154 of theheat shield 102 a; this length dimension being within/along the thirddimension 384).

Similarly, the base 304′ of the heat shield recess 300′ may becorrespondingly-shaped with and parallel to the second surface 308′ ofthe heat shield 102 b. The thickness of the heat shield 102 b within theheat shield recess 300′ is then at least substantially constantproceeding from the first heat shield end 152 to the second heat shieldend 154, which coincides with the direction of an induction weldingoperation using the heat shield 102 b. As such, the spacing between aninduction coil and the workpiece being induction welded remains at leastsubstantially constant as the induction coil moves along the lengthdimension of the heat shield recess 300′ during induction weldingoperations when using the heat shield 102 a (this length dimensioncoinciding with the spacing between the first heat shield end 152 andthe second heat shield end 154 of the heat shield 102 b; this lengthdimension being within/along the third dimension 384).

A schematic of an induction welding assembly is illustrated in FIG. 20and is identified by reference numeral 310. Unless otherwise notedherein to the contrary, features of the induction welders/weldingassemblies discussed above may be utilized by the induction weldingassembly 310 of FIG. 20 . The induction welding assembly 310 includes afirst support 370 a (e.g., one of the trunks 100), a second support 370b (e.g., another of the trunks 100), an induction welding coil 312(e.g., induction welding coil 38), a heat management device or heatshield 320, an optional heat management device 330 (e.g., bottom heatmanagement device 54), a workpiece zone 340 (e.g., workpiece receptacle70), and an actuator 360 (e.g., actuator 56). The heat shield 320 isdisposed between the induction welding coil 312 and the workpiece zone340 in the first dimension 380. Similarly, the heat shield 320 isdisposed between the workpiece zone 340 and supports 370 a, 370 b in thefirst dimension 380. The workpiece zone 340 is disposed between the heatshield 320 and the actuator 360 in the first dimension 380.

The heat shield 320 of the induction welding assembly 310 may be inaccord with the heat shield 102 a of FIG. 19A or the heat shield 102 bof FIG. 19B. In this regard, the heat shield 320 includes a heat shieldrecess 322 on a first surface 328 of the heat shield 320. The heatshield recess 322 is concave relative to the first surface 328, and iscollectively defined by a pair of sidewalls 324 and a base or bottom 326that extends between the sidewalls 324. The heat shield recess 322 isaligned with and projects toward the induction coil 312. During aninduction welding operation, the induction welding coil 312 will be atleast partially disposed within the heat shield recess 322. Typicallythere will be at least some space between the induction welding coil 312and the base 326 of the heat shield recess 322.

A workpiece 350 of any appropriate size, shape, configuration, and/ortype may be disposed within the workpiece zone 340. The illustratedworkpiece 350 includes a first workpiece member 352 and a secondworkpiece member 354 that are to be induction welded together (the notedoptional heat management device 330 may be correspondingly-shaped withthe workpiece 350). For instance, the first workpiece member 352 and thesecond workpiece member 354 may be thermoplastic structures. Theworkpiece 350 may be configured as a fan cowl for a nacelle of anaircraft propulsion system. The workpiece 350, however, mayalternatively be configured as or may otherwise be included as part ofanother nacelle component, an aircraft control surface, a wing or anaircraft fuselage. However, the induction welding assembly 310 is notlimited to induction welding and manufacturing such exemplary componentsor to aircraft propulsion system applications. For instance, theinduction welding assembly 310 may be utilized for manufacturing anytype or configuration of workpiece where two or more bodies (e.g.,workpiece members) are joined together via induction welding.

The first support 370 a engages the heat shield 320 on a first side ofthe heat shield recess 322, while the second support 370 b engages theheat shield 320 on an opposite second side of the heat shield recess322. The supports 370 a, 370 b may move toward and away from the heatshield 320 in the direction indicated by the corresponding double-headedarrow A in FIG. 20 . The supports 370 a, 370 b may engage the heatshield 320 in proximity to the heat shield recess 322. In accordancewith the discussion above regarding the heat shields 102 a, 102 b, thesurface of the heat shield 320 engaged by the supports 370 a, 370 b(outside the heat shield recesses 300, 300′, respectively) may becorrespondingly-shaped with the interfacing surfaces of these supports370 a, 370 b.

The actuator 360 provides a force in the direction indicated by thearrow B. This actuation force is opposed by the supports 370 a, 370 bengaging the heat shield 320 such that the first workpiece member 352and the second workpiece member 354 are compressed between the heatshield 320 and the actuator 360 (the supports 370 a, 370 b remaining ina fixed position while engaging the heat shield 320), although one ormore components may be disposed between the heat shield 320 and actuator360 in the first dimension 380 (e.g., the heat management device 330;one or more intermediate structures could be disposed between theactuator 360 and the workpiece 350).

The heat shield 320 may also be characterized as a low thermalconductive/low heat capacity part to reduce the potential for theworkpiece 350 cooling too rapidly). Moreover and as addressed below, theheat shield 320 may be characterized as being an electromagnetic (EM)transparent part.

There are a number of points of note regarding the induction weldingassembly 310 of FIG. 20 . The supports 370 a, 370 b engage the heatshield 320 at locations where the thickness of the heat shield 320 isgreater than the thickness of the heat shield 320 within the heat shieldrecess 322. This enhances the structural integrity of the heat shield320 during induction welding operations.

The heat shield recess 322 allows the induction welding coil 312 to bepositioned closer to the workpiece 350 (compared to if a heat shield ofuniform thickness is utilized; the heat shield recess 322 accommodatessufficient heat transfer for welding of the workpiece 350), and yetallows for the supports 370 a, 370 b to engage the heat shield 320 atlocations of enhanced thickness (compared to the thickness of the heatshield 320 within the heat shield recess 322). Again, the supports 370a, 370 b support the heat shield 320 as forces are transmitted to theheat shield 320 by the actuator 360 during induction welding operations.

In addition and as discussed above with regard to the heat shields 102a, 102 b, the base 326 of the heat shield recess 322 may becorrespondingly-shaped with and parallel to the surface of the heatshield 320 that interfaces with the optional heat management device 330(or that interfaces directly with the workpiece 350, namely the firstworkpiece member 352). The thickness of the heat shield 320 within theheat shield recess 322 is then at least substantially constantproceeding along the length dimension of the heat shield recess 322(into/out of the page in the view shown in FIG. 20 ; in the thirddimension 384 shown in FIGS. 19A and 19B), which coincides with thedirection of an induction welding operation. As such, the spacingbetween the induction coil 312 and the workpiece 350 being inductionwelded remains at least substantially constant as the induction coil 312moves along the length dimension of the heat shield recess 322 duringinduction welding operations (into/out of the page in the view shown inFIG. 20 ; in the third dimension 384 shown in FIGS. 19A and 19B).

The heat shield 320 provides a number of benefits in relation tooperation of the induction welding assembly 310 (these same benefitsapply whether the heat shield 320 is in the form of the heat shield 102a (FIG. 19A) or the heat shield 102 b (FIG. 19B)). One is that the heatshield 320 isolates the workpiece 350 (including the first workpiecemember 352) from cooling an undesired amount during induction weldingoperations. Another is that the heat shield 320 reduces the potential ofthe supports 370 a, 370 b (e.g., trunks) from overheating duringinduction welding operations.

The heat shield 320 may be formed from mica (e.g., machined or milledfrom a sheet or block of a sufficient thickness), which provides anumber of advantages for induction welding operations. One is that amica heat shield 320 does not conduct electromagnetic fields, andthereby should not interfere with induction welding operations. Anotheris that a mica heat shield 320 tolerates the processing temperaturesthat are used in induction welding operations (e.g., a mica heat shield320 is suitable for use in temperatures of at least 350° C.). Yetanother is that a mica heat shield 320 with the heat shield recess 322provides sufficient support for the workpiece 350 during inductionwelding operations (e.g., by the supports 370 a, 370 b engaging portionsof the heat shield 320 having an enhanced thickness compared to withinthe heat shield recess 322, and by such a mica heat shield 320 having ahigh compressive strength, for instance to withstand a pressure of atleast 90 psi). Other materials that are in accord with the foregoing(e.g., a sufficient tensile strength, machinability, availability in anappropriate thickness, transparent to electromagnetic fields) may beused for the heat shield 320.

An induction welding operation or method is illustrated in FIG. 21 , isidentified by reference numeral 400, and will be addressed in relationto the induction welding assembly 310 of FIG. 20 . A workpiece 350 isloaded in the workpiece zone 340 of the induction welding assembly 310(402). The first support 370 a engages the first surface 328 of the heatshield 320 on a first side of the heat shield recess 322, while thesecond support 370 b engages the first surface 328 of the heat shield320 on an opposite second side of the heat shield recess 322 (404). Thelocations where the supports 370 a, 370 b engage the heat shield 320will be spaced in the second dimension 382.

The induction welding coil 312 may be moved relative to the heat shield320 to position at least part of the induction welding coil 312 withinthe heat shield recess 322 (406). Typically the entirety of theinduction welding coil 312 will be spaced from the base or bottom 326 ofthe heat shield recess 322 when the induction welding coil 312 is inposition for induction welding.

The heat shield 320 may be forced against the supports 370 a, 370 b(408). For instance, the actuator 360 may be operated to exert a forceon the workpiece 350 that is in the direction of the heat shield 320.This force may compress the workpiece 350 between the heat shield 320and the actuator 360. Thereafter, the workpiece 350 may be inductionwelded in the manner described herein, and including via operation ofthe induction welding coil 312 (410).

The induction welding assembly 310 of FIG. 20 again may be used toinduction weld a first workpiece member 352 (e.g., a thermoplasticstructure) to a second workpiece member 354 (e.g., a thermoplasticstructure), for instance as at least part of the fabrication of a fancowl for a nacelle of an aircraft propulsion system. A stiffened panelhalf or panel 420 for such a fan cowl is illustrated in FIG. 22A. Thepanel 420 may include an outer skin 422. The outer skin 422 may be madefrom a fiber-reinforced thermoplastic material. In various embodiments,the outer skin 422 includes a continuous reinforcing fiber and athermoplastic resin. Any appropriate reinforcing fiber may be utilizedfor the outer skin 422. In any case, the outer skin 422 may have asemi-cylindrical geometry when viewed from the aft direction, extendingfrom an edge 426 a to an edge 426 b and as shown in the illustratedembodiment. The outer skin 422 may define a centerline axis 428. Stateddifferently, the outer skin 422 may be bent or curved around/about thecenterline axis 428 (e.g., extending 180° about the centerline axis428).

A section view of the panel 420 is illustrated in FIG. 22B. The outerskin 422 may be contoured along the longitudinal direction (i.e., theZ-direction). Stated differently, the outer skin 422 may have anon-linear geometry (e.g., curved or rounded) proceeding along alongitudinal direction of the outer skin 422 (the centerline axis 428extending in the longitudinal direction). One or more ribs or stiffeners430 may be mounted to an inner surface 424 of the outer skin 422 (notshown in FIG. 22A; each stiffener 430 being separately formed from theouter skin 422). The length dimension of each stiffener 430 may extendbetween the edges 426 a, 426 b of the outer skin 422 (e.g., the lengthdimension of each stiffener 430 may extend 180° about the centerlineaxis 428, although each stiffener 430 may be of any appropriate arcuateextent about the centerline axis 428). Each stiffener 430 may be of anyappropriate configuration (e.g., hat-shaped as shown in FIG. 22B;Z-shaped; C-shaped). Multiple stiffeners 430 may be spaced along thecenterline axis 428. Any appropriate number of stiffeners 430 may beutilized by the panel 420, including one or more stiffeners 430.

FIG. 23A illustrates an induction welding assembly that is a variationof the induction welding assembly 310 of FIG. 20 and that is identifiedby reference numeral 310 a. The primary difference between the inductionwelding assembly 310 a of FIG. 23A and the induction welding assembly310 of FIG. 20 is that the induction welding assembly 310 a of FIG. 23Autilizes a plurality of heat shields 102 b″ (where each such heat shield102 b″ is a variation of the heat shield 102 b of FIGS. 19B and 19C) toaccommodate induction welding a stiffener (e.g., stiffener 430—FIG. 22B)onto a curved skin or shell (e.g., outer skin 422—FIGS. 22A and 22B).The discussion presented above regarding the induction welding assembly310 of FIG. 20 remains equally applicable to the induction weldingassembly 310 a of FIG. 23A unless otherwise noted to the contraryherein. Moreover, corresponding components between the heat shield 102 bof FIGS. 19B and 19C and the heat shields 102 b″ of FIG. 23A areidentified by the same reference numbers, and unless otherwise noted tothe contrary herein, the discussion presented above with regard to thesecorresponding components remains equally applicable.

The cross section presented in FIG. 23A is of a view taken along thelength dimension of the heat shield recess 300′ of the heat shields 102b″ (e.g., along X-X in FIG. 20 , but where the heat shield 320 in FIG.20 is in the form of the heat shields 102 b″ presented in FIG. 23A). Asthe heat shield ends 152″, 154″ of the heat shields 102 b″ are notperpendicular to the first surface 306 of the heat shield 102 b″, a“double prime” designation is used in FIG. 23A. This is the primarydifference between the heat shields 102 b″ of FIG. 23A and the heatshield 102 b of FIGS. 19B and 19C. That is, the heat shield ends 152″,154″ are “angled” to accommodate a positioning of the multiple heatshields 102 b″ in a manner discussed below.

As noted above, the base 304′ of the heat shield recess 300′ for theheat shield 102 b″ is curved proceeding from the first heat shield end152″ to the second heat shield end 154″ (e.g., the base 304′ is curvedproceeding in the third dimension 384; the base 304′ may becharacterized as being a convex surface or convex proceeding in thethird dimension 384). The base 304′ of the heat shield recess 300′ couldbe configured so as to not be curved in the second dimension 382 (e.g.,the base 304′ could be cylindrical). Similarly, the second surface 308′of the heat shield 102 b″ is curved proceeding from the first heatshield end 152″ to the second heat shield end 154″ (e.g., the secondsurface 308′ is curved proceeding in the third dimension 384; the secondsurface 308′ may be characterized as being a concave surface or concaveproceeding in the third dimension 384). The second surface 308′ of theheat shield 102 b″ could be configured so as to not be curved in thesecond dimension 382 (e.g., the second surface 308′ could becylindrical). The base 304′ of the heat shield recess 300′ may becorrespondingly-shaped with second surface 308′ of the heat shield 102b″, including where the base 304′ of the heat shield recess 300′ is atleast substantially parallel to the second surface 308′ of the heatshield 102 b″ (e.g., a curvature of the base 304′ may match a curvatureof the second surface 308′ of the heat shield 102 b″).

The heat shields 102 b″ are at least generally aligned or disposed inend-to-end relation for the case of the induction welding assembly 310 apresented in FIG. 23A. In the case of adjacently-disposed heat shields102 b″, a first heat shield end 152″ of one of these heat shields 102 b″may be disposed in closely-spaced relation to or engaged with a secondheat shield end 154″ of the adjacently-disposed heat shields 102 b″. Inany case, the plurality of heat shields 102 b″ may be characterized as aheat shield assembly 440. Any appropriate number of heat shields 102 b″may be used by the heat shield assembly 440. Althoughadjacently-disposed first supports 370 a are illustrated as beingengaged, such need not be the case. Moreover, a single first support 370a could be configured to engage the corresponding portion of the firstsurface 306 of multiple heat shields 102 b″.

The length dimension of the heat shield assembly 440 may becharacterized as the spacing between a first end 442 of the heat shieldassembly 440 (corresponding with the first heat shield end 152″ of theheat shield 102 b″ at this first end 442) and a second end 444 of theheat shield assembly 440 (corresponding with the second heat shield end154″ of the heat shield 102 b″ at this second end 444), where thislength dimension proceeds about a reference axis 446 (e.g., thereference axis 446 may extend in the third dimension 384). The heatshield assembly 440 may be of any appropriate length proceeding aboutthis reference axis 446. For instance, the length dimension of the heatshield assembly 440 may extend 180° about the reference axis 446,although other angular extents (“angular” meaning about the axis 446) ofthe heat shield assembly 440 may be utilized as desired/required.

The bases 304′ of the heat shield recesses 300′ of the heat shields 102b″ of the heat shield assembly 440 may collectively extend about theabove-noted reference axis 446, including where these bases 304′collectively define an at least substantially continuous surface thatcurves proceeding about reference axis 446 (and including at a constantradius relative to this reference axis 446). The second surface 308′ ofeach heat shield 102 b″ of the heat shield assembly 440 may collectivelyextend about the reference axis 446, including where these secondsurfaces 308′ collectively define an at least substantially continuoussurface that curves proceeding about reference axis 446 (and includingat a constant radius relative to this reference axis 446). The secondsurface 308′ of each heat shield 102 b″ may be correspondingly-shapedwith a corresponding portion of the outer skin 422 of the panel 420(FIGS. 22A and 22B) for induction welding operations by the inductionwelding assembly 310 a.

The induction welding coil 312 (FIG. 20 ) moves along a curved weldingpath 314 during induction welding operations using the induction weldingassembly 310 a of FIG. 23A (the induction welding coil 312 may move ineither direction along this curved welding path 314 during inductionwelding operations). This curved welding path 314 may also proceed aboutthe above-noted reference axis 446, including where the curved weldingpath 314 is defined by a fixed radius extending from the reference axis446. The base 304′ of each heat shield 102 b″ may be at leastsubstantially parallel with the noted curved welding path 314. In anycase, the induction welding coil 312 may remain at an at leastsubstantially common, fixed distance from the bases 304′ of the heatshield recesses 300′ for the heat shields 102 b″ as the inductionwelding coil 312 moves along the curved welding path 314 (e.g.,proceeding from the first end 442 of the heat shield assembly 440 to thesecond end 444 of the heat shield assembly 440, or vice versa).

The induction welding assembly 310 a of FIG. 23A may be used toinduction weld one or more stiffeners 430 (FIG. 22B) to the innersurface 424 of the outer skin 422 (FIG. 22B). Referring back to FIG.22B, the stiffener 430 includes a pair of flanges 432. A sidewall 434 ofthe stiffener 430 extends between each of its flanges 432 and an endwall 436 of the stiffener 430. The stiffener 430 thereby includes ahollow interior 438 that is collectively defined by the two sidewalls434 and the end wall 436.

Each flange 432 of the stiffener 430 may be induction welded to theinner surface 424 of the outer skin 422 (FIG. 22B) by the inductionwelding assembly 310 a (FIG. 23A). The stiffener 430 (e.g., a secondworkpiece member 354— FIG. 20 ) and panel 420 (e.g., a first workpiecemember 352— FIG. 20 ) may be positioned relative to the inductionwelding assembly 310 a such that the centerline axis 428 (FIGS. 22A and22B) is colinear with or parallel to the reference axis 446 associatedwith the heat shield assembly 440 of the induction welding assembly 310a. One of the flanges 432 would be aligned with at least one heat shieldrecess 300′ of the heat shield assembly 440, the induction welding coil312 (FIG. 20 ) of the induction welding assembly 310 a would be directedinto the aligned heat shield recess 300′ of at least one heat shield 102b″, and the induction welding coil 312 would be moved along the curvedwelding path 314 (and along/within the various heat shield recesses300′) to induction weld the noted flange 432 to the inner surface 424 ofthe outer skin 422. Movement of the induction welding coil 312 along thecurved welding path 314 may be terminated once the flange 432 of thestiffener 430 has been induction welded to the inner surface 424 of theouter skin 422 to the desired extent, the induction welding coil 312 maybe moved away from the heat shield assembly 440 (such that the inductionwelding coil 312 does not extend into the heat shield recess 300′ of anyof the heat shields 102 b″), and the induction welding assembly 310 amay be repositioned relative to the stiffener 430 and panel 420 to alignthe other flange 432 of the stiffener 430 with at least one heat shieldrecess 300′ of the heat shield assembly 440 of the induction weldingassembly 310 a. This second flange 432 of the stiffener 430 may then beinduction welded to the inner surface 424 of the outer skin 422 inaccordance with the foregoing.

FIG. 23B illustrates an induction welding assembly that is a variationof the induction welding assembly 310 of FIG. 20 and that is identifiedby reference numeral 310 b. The primary difference between the inductionwelding assembly 310 a of FIG. 23B and the induction welding assembly310 of FIG. 20 is that the induction welding assembly 310 b of FIG. 23Butilizes a plurality of heat shields 102 b (FIG. 19A) to accommodateinduction welding the first workpiece member 352 to the second workpiecemember 354. The discussion presented above regarding the inductionwelding assembly 310 of FIG. 20 remains equally applicable to theinduction welding assembly 310 b of FIG. 23B unless otherwise noted tothe contrary herein.

The cross section presented in FIG. 23B is of a view taken along thelength dimension of the heat shield recess 300 of the heat shields 102 a(e.g., along X-X in FIG. 20 , but where the heat shield 320 in FIG. 20is in the form of the heat shields 102 a presented in FIG. 23B). Theheat shields 102 a are at least generally aligned or disposed inend-to-end relation for the case of the induction welding assembly 310 bpresented in FIG. 23B. In the case of adjacently-disposed heat shields102 a, a first heat shield end 152 of one of these heat shields 102 amay be disposed in closely-spaced relation to or engaged with a secondheat shield end 154 of the adjacently-disposed heat shields 102 a. Inany case, the plurality of heat shields 102 a may be characterized as aheat shield assembly 440′. Any appropriate number of heat shields 102 amay be used by the heat shield assembly 440′. Althoughadjacently-disposed first supports 370 a are illustrated as beingengaged, such need not be the case. Moreover, a single first support 370a could be configured to engage the corresponding portion of the firstsurface 306 of multiple heat shields 102 a.

The length dimension of the heat shield assembly 440′ may becharacterized as the spacing between a first end 442 of the heat shieldassembly 440 (corresponding with the first heat shield end 152 of theheat shield 102 a at this first end 442) and a second end 444 of theheat shield assembly 440′ (corresponding with the second heat shield end154 of the heat shield 102 a at this second end 444), where this lengthdimension coincides with the third dimension 384. The heat shieldassembly 440′ may be of any appropriate length in the third dimension384.

As noted above, the base 304 of the heat shield recess 300 is flat orplanar. The bases 304 of the heat shield recesses 300 of the heatshields 102 a of the heat shield assembly 440′ may be aligned for theirrespective lengths to collectively extend in the third dimension 384.The bases 304 of the various heat shields 102 a may collectively definean at least substantially continuous surface that is flat or planar.

The induction welding coil 312 (FIG. 20 ) moves along an axial or linearwelding path 316 during induction welding operations using the inductionwelding assembly 310 b of FIG. 23B (the induction welding coil 312 maymove in either direction along this axial welding path 316 duringinduction welding operations). This axial welding path 316 may extend inthe third dimension 384. The induction welding coil 312 may remain at anat least substantially common fixed distance from the bases 304 of theheat shield recesses 300 for the heat shields 102 a as the inductionwelding coil 312 moves along the axial welding path 316 (e.g.,proceeding from the first end 442 of the heat shield assembly 440′ tothe second end 444 of the heat shield assembly 440′, or vice versa).

A schematic of an induction welding assembly is illustrated in FIG. 24and is identified by reference numeral 800. Unless otherwise notedherein to the contrary, features of the induction welder/weldingassemblies/induction welding methods discussed above may be utilized bythe induction welding assembly 800 of FIG. 24 . The induction weldingassembly 800 may comprise an induction welding coil 312 of FIG. 20 , aheat shield 802, and a workpiece zone 804. The heat shield 802 may bedisposed between the induction welding coil 312 of FIG. 20 (or as shownin FIG. 24 , a support block 806) and the workpiece zone 804 in a firstdimension 380. In various embodiments, an induction welding assembly maycomprise a plurality of heat shields aligned in end-to-end relation. Theheat shield 802 may comprise mica (e.g., machined or milled from a sheetor block of sufficient thickness). In various embodiments, materialsthat are in accord with the foregoing (e.g., a sufficient tensilestrength, machinability, availability in an appropriate thickness,transparent to electromagnetic fields) may be used for the heat shield802.

As previously discussed, a mica heat shield 802 does not conduct anelectromagnetic field (thereby not interfering with induction weldingoperations) and may tolerate the processing temperatures that are usedin induction welding operations (e.g. greater than 350 degreesFahrenheit). The mica heat shield 802 may comprise areas of thinnerportions (e.g., a heat shield recess 807), or thicker portionsconfigured to provide sufficient support for a workpiece or plurality ofworkpieces (e.g., first workpiece 808 a and second workpiece 808 b)during induction welding operations. In various embodiments, the firstworkpiece 808 a may be a thermoplastic panel and the second workpiece808 b may be a stiffener.

In various embodiments, the mica heat shield 802 may comprise a weldingpath that is axially extending or curved, depending on the surface ofthe workpiece or workpieces. For example, the heat shield 802 may becurved, providing a curved welding path for induction welding operationsalong a curved surface, such as a fan cowl or fuselage of an aircraft.

During induction welding of thermoplastic structures, the mica heatshield 802 may tend to flake or degrade. This may be caused by weldingtemperatures that may be at or around, or above, 700 degrees Fahrenheit(371 degrees Celsius). Flaking may damage the heat shield 802 andworkpieces 808 a or 808 b. Moreover, such high temperatures may causethe mica heat shield 802 to attach or bond to a material substrate, suchas the surface of a thermoplastic workpiece.

It may be advantageous to create a barrier between the mica heat shield802 and workpieces in the workpiece zone 804 that does not interferewith induction welding operations or heat shield function. Accordingly,as shown in FIG. 25 , the heat shield 802 may comprise a ceramic coating809 (illustrated as a ceramic coating layer applied onto the heatshield) to prevent the heat shield 802 from flaking during inductionwelding operations or prevent bonding of the heat shield 802 to aworkpiece during induction welding operations. In various embodiments,the ceramic coating 809 may be brushed, sprayed, or applied onto theheat shield in any suitable manner. The ceramic coating 809 may be amore advantageous barrier compared to a heat-resistant film barrier,which may fuse to a workpiece or heat shield during induction weldingoperations.

Similar to the mica heat shield 802, the ceramic coating 809 may be anon-conductor of an electromagnetic field (e.g., electromagneticallytransparent) so as not to interfere with induction welding operations.Moreover, the ceramic coating 809 may enhance the heat resistance of theheat shield 802. The ceramic coating 809 may have a heat resistancebetween 300 degrees and 500 degrees Fahrenheit (148 degrees and 260degrees Celsius), 500 degrees and 800 degrees Fahrenheit (260 and 426degrees Celsius), 800 degrees and 1,500 degrees Fahrenheit (426 degreesand 816 degrees Celsius), and 1,500 degrees and 3,800 degrees Fahrenheit(816 degrees and 2,094 degrees Celsius). In various embodiments, theceramic coating 809 may advantageously have a heat resistance greaterthan 900 degrees Fahrenheit (482 degrees Celsius). In variousembodiments, the ceramic coating 809 may be a high-temperature ceramiccoating with a heat resistance of up to 5,000 degrees Fahrenheit (2,760degrees Celsius). Accordingly, and as further shown in FIG. 26A, theceramic coating 809 may be applied to an area of the heat shield whereinduction welding may occur, such as the heat shield recess 807. Invarious embodiments, and as further shown in FIG. 26B, the ceramiccoating 809 may be applied to the all or part of the heat shield 802.

In various embodiments, the ceramic coating 809 may be an acrylic,silicone, or elastomeric based coating, and the like. The ceramiccoating 809 may be formulated using acrylic resins, silicone resins,elastomeric resins, and the like. The ceramic coating 809 may be asingle type of ceramic coating, or a homogenous mixture of at least twoceramic coating types. In various embodiments, the ceramic coating 809may comprise additives to enhance anti-flaking properties of the heatshield 802 and/or to further prevent bonding of the workpiece 808 aand/or 808 b to the heat shield 802. For example, in some embodiments,the ceramic coating 809 may further comprise polytetrafluoroethylene(PTFE) synthetic fluoropolymer. The ceramic coating 809 may comprisePTFE in liquid form as part of a homogenous mixture. In variousembodiments, the ceramic coating 809 may comprise PTFE chips mixed intothe ceramic coating 809. PTFE may be an advantageous additive forpreventing sticking or bonding of the heat shield 802 to the workpiece808 a and/or 808 b.

In various embodiments, the ceramic coating 809 may comprise a mixtureof polymer emulsions and mineral fillers. For example, the ceramiccoating 809 may comprise water, acrylic (e.g., a polymer portion), andcalcium carbonate (e.g., a mineral filler). The chemical composition ofsuch ceramic coating may be greater than 25% water, less than 25%acrylic, and greater than 50% calcium carbonate. In various embodiments,the polymer portion of the ceramic coating 809 may comprise silicone orelastomeric resins in lieu of acrylic or may comprise variouscombinations thereof. In various embodiments, the mineral filler may beDolomite (calcium magnesium carbonate). In various embodiments, themineral filler may be a combination of Dolomite and calcium carbonate.Dolomite and/or calcium carbonate may be utilized as fillers due totheir heat resistance characteristics.

Any feature of any other various aspects addressed in this disclosurethat is intended to be limited to a “singular” context or the like willbe clearly set forth herein by terms such as “only,” “single,” “limitedto,” or the like. Merely introducing a feature in accordance withcommonly accepted antecedent basis practice does not limit thecorresponding feature to the singular. Moreover, any failure to usephrases such as “at least one” also does not limit the correspondingfeature to the singular. Use of the phrase “at least substantially,” “atleast generally,” or the like in relation to a particular featureencompasses the corresponding characteristic and insubstantialvariations thereof (e.g., indicating that a surface is at leastsubstantially or at least generally flat encompasses the surfaceactually being flat and insubstantial variations thereof). Finally, areference of a feature in conjunction with the phrase “in oneembodiment” does not limit the use of the feature to a singleembodiment.

The foregoing description has been presented for purposes ofillustration and description. Furthermore, the description is notintended to limit the invention to the form disclosed herein.Consequently, variations and modifications commensurate with the aboveteachings, and skill and knowledge of the relevant art, are within thescope of the present disclosure. Benefits, other advantages, andsolutions to problems have been described herein with regard to specificembodiments. Furthermore, the connecting lines shown in the variousfigures contained herein are intended to represent exemplary functionalrelationships and/or physical couplings between the various elements. Itshould be noted that many alternative or additional functionalrelationships or physical connections may be present in a practicalsystem. However, the benefits, advantages, solutions to problems, andany elements that may cause any benefit, advantage, or solution to occuror become more pronounced are not to be construed as critical, required,or essential features or elements of the disclosure. The scope of thedisclosure is accordingly to be limited by nothing other than theappended claims, in which reference to an element in the singular is notintended to mean “one and only one” unless explicitly so stated, butrather “one or more.” Moreover, where a phrase similar to “at least oneof A, B, or C” is used in the claims, it is intended that the phrase beinterpreted to mean that A alone may be present in an embodiment, Balone may be present in an embodiment, C alone may be present in anembodiment, or that any combination of the elements A, B and C may bepresent in a single embodiment; for example, A and B, A and C, B and C,or A and B and C. Different cross-hatching is used throughout thefigures to denote different parts but not necessarily to denote the sameor different materials.

Systems, methods and apparatus are provided herein. In the detaileddescription herein, references to “one embodiment,” “an embodiment,”“various embodiments,” etc., indicate that the embodiment described mayinclude a particular feature, structure, or characteristic, but everyembodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a particular feature,structure, or characteristic is described in connection with anembodiment, it is submitted that it is within the knowledge of oneskilled in the art to affect such feature, structure, or characteristicin connection with other embodiments whether or not explicitlydescribed. After reading the description, it will be apparent to oneskilled in the relevant art(s) how to implement the disclosure inalternative embodiments.

Furthermore, no element, component, or method step in the presentdisclosure is intended to be dedicated to the public regardless ofwhether the element, component, or method step is explicitly recited inthe claims. No claim element herein is to be construed under theprovisions of 35 U.S.C. 112(f) unless the element is expressly recitedusing the phrase “means for.” As used herein, the terms “comprises,”“comprising,” or any other variation thereof, are intended to cover anon-exclusive inclusion, such that a process, method, article, orapparatus that comprises a list of elements does not include only thoseelements but may include other elements not expressly listed or inherentto such process, method, article, or apparatus. Finally, it should beunderstood that any of the above described concepts can be used alone orin combination with any or all of the other above described concepts.Although various embodiments have been disclosed and described, one ofordinary skill in this art would recognize that certain modificationswould come within the scope of this disclosure. Accordingly, thedescription is not intended to be exhaustive or to limit the principlesdescribed or illustrated herein to any precise form. Many modificationsand variations are possible in light of the above teaching.

1. An induction welding assembly, comprising: an induction welding coil;a heat shield comprising: a ceramic coating; and a heat shield recessaligned with and projecting toward said induction welding coil; and aworkpiece zone, wherein said heat shield is disposed between saidinduction welding coil and said workpiece zone in a first dimension. 2.The induction welding assembly of claim 1, wherein said ceramic coatinghas a heat resistance greater than 900 degrees Fahrenheit, wherein saidceramic coating is a non-conductor of an electromagnetic field.
 3. Theinduction welding assembly of claim 1, wherein said ceramic coating isdisposed along said heat shield recess.
 4. The induction weldingassembly of claim 1, wherein the ceramic coating is a homogenous mixtureof at least two coatings.
 5. The induction welding assembly of claim 4,wherein the ceramic coating further comprises a polytetrafluoroethylenesynthetic fluoropolymer.
 6. The induction welding assembly of claim 1,wherein said heat shield comprises mica.
 7. The induction weldingassembly of claim 1, wherein said heat shield is a non-conductor of anelectromagnetic field.
 8. The induction welding assembly of claim 1,wherein the heat shield comprises a first heat shield end and a secondheat shield end, said heat shield recess extending between said firstand second heat shield ends and projecting away from said workpiecezone, wherein the heat shield recess is configured to provide a weldingpath for said induction welding coil.
 9. The induction welding assemblyof claim 8, wherein said heat shield recess comprises a pair ofsidewalls and a base that extends between each sidewall of said pair andthat further extends between said first and second heat shield ends. 10.The induction welding assembly of claim 9, wherein said inductionwelding coil is at least partially disposed within said heat shieldrecess and is spaced from said base.
 11. The induction welding assemblyof claim 9, wherein said base is axially extending between said firstand second heat shield ends.
 12. The induction welding assembly of claim9, wherein said base is curved proceeding between said first and secondheat shield ends.
 13. The induction welding assembly of claim 9, whereinthe heat shield comprises a thickness within the heat shield recess thatis at least substantially constant proceeding between said first andsecond heat shield ends.
 14. An induction welding assembly, comprising:an induction welding coil; a heat shield assembly comprising a pluralityof heat shields aligned in end-to-end relation, wherein each heat shieldof said plurality of heat shields comprises a heat shield recess,wherein each heat shield recess of said plurality of heat shieldscomprises a ceramic coating, and wherein said heat shield recesses ofsaid plurality of heart shields are aligned to provide a welding pathfor said induction welding coil; and a workpiece zone, wherein said heatshield assembly is disposed between said induction welding coil and saidworkpiece zone in a first dimension.
 15. The induction welding assemblyof claim 14, wherein said welding path is axially extending.
 16. Theinduction welding assembly of claim 14, wherein said welding path iscurved.
 17. An induction welding method, comprising: positioning aworkpiece such that a heat shield is disposed between said workpiece andan induction welding coil, wherein said induction welding coil is atleast partially disposed in a heat shield recess of said heat shield,wherein said heat shield recess comprises a ceramic coating, and whereinsaid workpiece comprises a first workpiece member and a second workpiecemember; advancing said induction welding coil along a welding path alongthe heat shield, wherein a spacing between said induction welding coiland said heat shield remains at least substantially constant during saidadvancing; and operating said induction welding coil to induction weldsaid first workpiece member to said second workpiece member.
 18. Aninduction welding method of claim 17, wherein said first workpiecemember comprises a panel and said second workpiece member comprises astiffener.
 19. The induction welding method of claim 18, wherein saidpanel is curved about a reference axis such that said advancing is alsoat least generally about said reference axis, wherein said advancing isat least generally along a length dimension of said stiffener.
 20. Theinduction welding method of claim 19, wherein said stiffener comprises aflange and said operating comprises induction welding said flange tosaid panel.